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1.
Inhaltsübersicht. Erstmals wurden klar durchscheinende, orange-farbene Einkristalle von Cs2Li14[Tb3O14] aus Cs2TbO3 und Li2O (Tb: Li = 1:5) dargestellt [550°C, 21 d, verschlossenes AuRohr]. Es liegt der K2Li14[Pb3O14]-Typ vor [Vierkreisdiffraktometerdaten, PW 1100, MoKä-Strahlung, 660 Io(hkl), R = 4,8%, Rw = 3,4%, Immm, a = 1293,5(8), b = 792,6(3), c = 740,4(3) pm, Z = 2, d = 4,65]. Ebenfalls neu wurde K2Li14[Zr3O14] in Form farbloser Einkristalle durch Tempern inniger Gemenge von K2O, Li2O und ZrO2 (K: Li: Zr = 1:4:1,5) dargestellt [900°C, 14 d, geschlossene Ni-Bombe] und röntgenographisch untersucht. Die Strukturverfeinerung [612 Io(hkl), Vierkreisdiffraktometerdaten, PW 1100, MoKα-Strahlung, R = 5,9%, Rw = 5,3%, Immm, a = 1244,6, b = 776,4, c = 724,3 pm, Z = 2] bestätigt die Isotypie mit K2Li14[Pb3O14]. Der Madelunganteil der Gitterenergie, MAPLE, Effektive Koordinationszahlen, ECoN, diese über Mittlere Effektive Ionenradien, MEFIR, wurden berechnet. Für die nun bekannten Vertreter dieses Typs wurde ein Isotypievergleich vorgenommen. New Compounds of the K2Li14[Pb3O14] Type: Cs2Li14[Tb8O14] and K2Li14[Zr3O14] For the first time Cs2Li14[Tb3O14] has been prepared as orange single crystals from Cs2TbO3 and Li2O (Tb: Li = 1:5) [550°C, 21 d, sealed Au-Tube]. Structure Refinement [four-circle diffractometer data, PW 1100, MoKα radiation, 660 Io(hkl), R = 4.8%, Rw = 3.4%, Immm, a = 1293.5(8), b = 792.6(3), c = 740.4(3) pm, Z = 2, d = 4.65] confirms isotypy with K2Li14[Pb3O14]. K2Li14[Zr3O14] has also been prepared as colorless single crystals from K2O, Li2O, and ZrO2 (K: Li: Zr = 1:4:1.5), [900°C, 14 d, closed Ni-cylinder] and investigated by x-ray [612 Io(hkl), four-circle diffractometer data, PW 1100, MoKα radiation, R = 5.9%, Rw = 5.3%, Immm, a = 1244.6, b = 776.4, c = 724.3 pm, Z = 2]. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, the latter derived from Mean Effective Fictive Ionic Radii, MEFIR, are calculated. A detailed comparison of the structures is carried out.  相似文献   

2.
Li2H4I2O10, the First Tetrahydrogendimesoperiodate Li2H4I2O10 has been obtained as an intermediate during the dehydration of LiH4IO6 · H2O to LiIO4, for the first time. According to the results of an X-ray structure determination (monoclinic, P21/n, a = 533.98(4), b = 471.85(4), c = 1431.48(10) pm, β = 91.614(7)°, Z = 2, 726 diffractometer data, R = 0.056), Li2H4I2O10 contains the previously unknown tetrahydrogendimesoperiodate ion H4I2O102?, consisting of two edge-shared IO6 octahedra. They are connected with LiO6 octahedra via common edges and vertices. The crystals are non-merohedrally twinned along (100).  相似文献   

3.
New Oxoterbates(IV) with Lithium: On Rb2Li14[Tb3O14] and Li6Tb2O7 For the first time we prepared Rb2Li14[Tb3O14] as yellow single crystals from Li8TbO6 and Rb2O (Tb:Rb = 1:2) [Ag-cylinder, 500°C, 30 d, then Au-tube, 700°C, 27 d]. The structure refinement [652 I0 (h kl), four circle diffractometer Philips PW 1100, ω-scan, MoKα, R = 4.69%, Rw = 3.24%, absorption considered, Immm with a = 1 283.07(10), b = 790.87(7), c = 736.87(7)pm, Z = 2, dx = 4.30 g · cm?3] confirms that it is isotypic with K2Li14[Pb3O14]. Furthermore we got for the first time Li6Tb2O7 as a bright yellow compound from Li2O2 and “Tb4O7*” [(Li:Tb = 3.4:1), Au-ube, 750°C, 13 d (powder), 850°C 22 d (single crystals)] and by thermal decomposition of Rb2Li14[Tb3O14] (Au-tube, 850°C, 25 d). Powder and single crystal data [1 327 I0 (h kl), four circle diffractometer PW 1100, ω-scan, AgKα, R = 9.38%, Rw = 5.23%, absorption not considered, P21/a, a = 1 056.30(10), b = 613.50(4), c = 546.56(5) pm, β = 109.668(7)°, Z = 2, dx = 4.67 g · cm?3 dpyc = 4.53 g · cm?3] reveal a new type of structure that may be deduced by the NaCl-type of structure. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated and discussed.  相似文献   

4.
Transition Metal Peroxofluoro Complexes. III. Preparation, Crystal Structure, and Vibrational Spectra of K6Ta3(O2)3OF13 · H2O Containing a m?-Oxo-diperoxo-octafluoroditantalate(V) Anion K6Ta3(O2)3OF13 · H2O has been prepared from solution and his crystal structure was determined by X-ray single crystal investigation: Space group Pnma, lattice constants a = 1 653.6 pm, b = 883.5 pm, c = 1 365.8 pm, Z = 4, R = 0.033. The compound yields [Ta(O2)F5]2? groups as well as m?-oxo-bridged [Ta2O(O2)2F8]4? anions with very diffrent O? O distances within the peroxo groups (139 pm vs. 164 and 175 pm) correlating well with the i.r. and Raman spectra. The different bonding in connection with an oxo-bridge is discussed.  相似文献   

5.
A New Oxomanganate(II): Na3Li5Mn5O9 Na3Li5Mn5O9 (orange-coloured, transparent single crystals) has been prepared for the first time, it crystallizes trigonal (R3 m) with a = 335.6 pm, c = 2612.0 pm, Z = 1, R = 4.4%, Rw = 3.6% for 159 I0(hkl) of 162 I0(hkl). The structure refinement led to a statistically distribution of 5 Mn2+ and 5 Li+ each in a sixfold position, according to Na3(Li5□)(Mn5□)O9. The structure can be described by closest packings of spheres. Several models for the calculation of the Madelung Part of Lattice Energy, MAPLE, are discussed.  相似文献   

6.
The First Oligooxoindate(III): K14[In4O13] For the first time K14[In4O13] was obtained by heating intimate mixtures of K2O, CdO and elementar In (molar ratio 3.1:1.0:1.0) in closed Ag-cylinders (30 days, 450°C) in form of yellow-brown single crystals. The structure determination by four circle diffractometer data MoKα, 3 689 out of 3 689 Io(hkl), R = 4.22, Rw = 2.45) confirms the space group P21/c with lattice constants a = 687.7 pm; b = 3 118.5 pm; c = 686.4 pm; β = 119.3°; Z = 2. The characteristic feature of the structure is [In4O13]14? groups, oligomers consisting of four corner-sharing InO4 tetrahedra. These groups are connected by crystallographically distinct potassium atoms. The structure is isotypic with Na14[Al4O13] [2] and K14[Fe3O13] [3]. ECoN and MAPLE calculationes are discussed.  相似文献   

7.
A New Oxouranate(VI): K2Li4[UO6]. With a Remark about Rb2Li4[UO6] and Cs2Li4[UO6] For the first time K2Li4UO6 has been prepared by an exchange reaction of α-Li6UO6 with K2O [K:U = 2.0:1, sealed au-tube; 750°C; 30 d single crystals; 680°C, 10 d powder]. The irregular shaped single crystals, which are of yellow color and sensitive to moisture crystallize in P3 m1 (Z = 1) with a = 619.27(5), c = 533.76(6) pm. The structure determination (PW 1100, AgKα R = 4.80%, Rw = 4.81% for 220 unique reflexions) reveals a new type of structure. The characteristic elements are the isolated group [UO6] and the C.N. = 12 for K+. While Li(1) has a nearly regular square of 4 O2? as coordination polyhedron, Li(2) is octahedrally surrounded. The Madelung Part of Lattice Energy (MAPLE) is calculated and discussed. In addition to K2Li4[UO6] the new oxides Rb2Li4[UO6] and Cs2Li4[UO6] are prepared as pale yellow powders which are little sensitive to moisture (both: au-tube, 680°C, 10 d). According to powder datas both compounds are isotypic with K2Li4[UO6] [Rb2Li4[UO6]: a = 622.91(5), c = 535.93(6) pm; Cs2Li4[UO6]: a = 626.70(6), c = 539.92(6) pm].  相似文献   

8.
Li6[TeMo6O24] · 18 H2O is triclinic (space group P1 , a = 1 041.7(1), b = 1 058.6(1), c = 1 070.8(1) pm, α = 61.08(1), β = 60.44(1), γ = 73.95(1)°). Single crystal X-ray structure analysis (Z = 1, 295 K, 317 parameters, 3 973 reflections, Rg = 0.0250) revealed an infinite branched chain of edge-sharing Li coordination polyhedra to be the prominent structural feature. One of the four crystallographically independent Li+ is coordinated octahedrally. The coordination polyhedra of the remaining Li+ are distorted trigonal bipyramids. Only three unique oxygen atoms (O(9), O(10), O(12)) of the centrosymmetric [TeMo6O24]6? anion are bound to Li+. The further positions in the coordination spheres of the Li+ are occupied by water molecules. Intermolecular hydrogen bonds involve mainly oxygen atoms of the [TeMo6O24]6? anion as nearly equivalent proton acceptors without regard to their different bonding modes to Te and Mo, respectively. Li6[TeMo6O24] · Te(OH)6 · 18 H2O crystallizes monoclinically in space group P21/n with Z = 4, a = 994.1(3), b = 2 344.8(10), c = 1 764.9(4) pm, and β = 91.36(4)°. Single crystal structure analysis with least squares refinement of 627 parameters (5 900 reflections, 295 K) converged to Rg = 0.0324. There are six unique Li+ cations. The coordination polyhedra of Li(1), Li(2), Li(3), and Li(4) are linked by common edges to yield an eight membered centrosymmetric strand. The coordination polyhedra of the remaining two Li+ sites (Li(5), Li(6)) are connected to a dimeric unit via a common corner. All oxygen atoms of the Te(OH)6 molecule are involved in the coordination of Li+. However, only three oxygen atoms (O(13), O(18), O(23)) of the [TeMo6O24]6? anion which lacks crystallographic symmetry are involved in the coordination of Li+. The oxygen atoms of the anion act as proton acceptors in hydrogen bonds of predominantly medium strength. Te(OH)6 molecules and [TeMo6O24]6? anions connected by strong hydrogen bonds form an infinite chain.  相似文献   

9.
Chains consisting of Rings: K5{Li[Ge2O7]} — the First ‘Litho-Digermanate’ By heating of a well-ground mixture of the binary oxides KO0.55, Li2O and GeO2 (K: Li: Ge = 6.1 : 2.2 : 2; Ni-tube; 600°C; 49 d) we obtained for the first time single crystals of K5{Li[Ge2O7]}. This ‘lithodigermanate’ represents a completely new type of structure: monoclinic, space group P21/c, a = 624.9(2) pm, b = 1586.6(8) pm; c = 1058.3(6) pm and β = 109.38(4)°; Guinier-Simon data, Z = 4. The structure was solved by four-circle diffractometer data [Siemens AED II, Mo? Kα ; 2872 Io(hkl); R = 4.5%, Rw = 3.3%], parameters see text. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, these calculated via Mean Fictive Ionic Radii, MEFIR, as well as charge distribution CHARDI, are calculated and discussed.  相似文献   

10.
Preparation of Crystal Structure of K6[Al2O6] and Rb6[Al2O6] Colourless single crystals of K6[Al2O6] have been prepared from intimate mixtures of KAlO2 and K2O (550°C, 90 d). The structure determination from four-circle diffractometer data (MoKα , 742 Io(hkl), R = 2.2%, Rw = 2.1%) confirms the space group C2/m with Z = 2; a = 698.25 pm, b = 1 103.54 pm, c = 646.49 pm, β = 102.49°. Colourless single crystals of hitherto unknown Rb6[Al2O6] have been prepared from intimate mixtures of RbAlO2 and Rb2O (520°C, 120 d). The structure determination from four-circle diffractometer data (MoKα , 1 240 Io(hkl)) results in the residual values R = 7.2%, Rw = 4.9%; space group C2/m; a = 725.92 pm, b = 1 143.33 pm, c = 678.06 pm, β = 104.05°; Z = 2. K6[Al2O6] and Rb6[Al2O6] are isostructural with K6[Fe2O6]. A characteristic structure unit is the anion [Al2O6]6? consisting of two edge-sharing [AlO4] tetrahedra. Effective Coordination Numbers (ECoN), Mean Fictive Ionic Radii (MEFIR), the Madelung Part of Lattice Energy (MAPLE) and the Charge Distribution (CHARDI) are calculated and discussed.  相似文献   

11.
Inhaltsübersicht. Bei Versuchen zur Darstellung unbekannter Phasen im System A/Au/I/O (mit A = Alkalimetall) entstanden durch Erhitzen eines Gemenges (2,2 K2O + 1,0 NaIO4; Au-Rohr; 700°C, 59 d) farblose, transparente Einkristalle von K6NaAu2IO8, das nach Einkristalldaten (Vierkreisdiffraktometerdaten, 2465 Io(hkl), AgKα, R = 6,8% und Rw = 5,6%) monoklin in P2/c mit a = 707,4 pm; b = 977,3 pm; c = 1199,4 pm; β = 122,9°; Z = 2 kristallisiert. Charakteristisch sind die hier erstmals gefundenen, HgO-analogen Zickzackketten [AuO2/2] längs [001]. Daneben prägen, den NaIO6-Teil der Struktur betreffend, Ketten aus [IO6]-Oktaeder, über Na in prismatischer Koordination verknüpft, den Aufbau. The First Quinquinary Oxoaurate(I). K6Na[IO6][AuO]2 = K6[NaIO6][AuO2/2]2 Attempting to synthesize unknown phases in the system A/Au/I/O by heating a mixture of K2O and NaIO4 (K: Na = 2.2:1.0, sealed gold tube, 700°C) we obtained colourless, transparent single crystals of K6NaAu2IO6, a new type of Oxoaurate(I). According to single crystal data K6NaAu2IO8 crystallizes in a monoclinic form with a = 707.4 pm, b = 977.3 pm, c = 1199.4 pm β = 122.9° (Z = 2, space group P2/c). Essential part of the structure are chains NaIO6 and zigzag chains AuO2/2, both along [001]. The Madelung part of the lattice energy, MAPLE, and effective coordination numbers, ECoN, are calculated and discussed.  相似文献   

12.
The First Oxocobaltate(II) with Dinuclear Anion: Rb2Na4[Co2O5] and K2Na4[Co2O5] By heating of well ground mixtures of the binary oxides [A2O, Na2O, ?CoO”?, A:Na:Co = 1.00:2.00:1, (A = K, Rb); Ag-tube, 600°C, 14 d] we obtained Rb2Na4[Co2O5] and K2Na4[Co2O5] rough, transparent, red single crystals. We find a new type of structure with the anion [O2CoOCoO2]6?. Space group P42/mnm; a = 634.4 pm, c = 1030.3 pm, Z = 2 (A = K) a = 647.6 pm, c = 1021.1 pm, Z = 2 (A = Rb); four-circle diffractometer data; MoKα -radiation; 360 from 364 I0(hkl), R = 4.34%, Rw = 3.54% (A = K); 361 from 366 I0(hkl), R = 6.54%, Rw = 2.70% (A = Rb). The anion is planar, the CN of Co is 3. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, are calculated and discussed.  相似文献   

13.
Li2H3IO6, a New Variant of the Molybdenite Structure Li2H3IO6 crystallizes in P61 (a = 529.70(8), c = 2 759.6(5) pm; Z = 6). The crystals are twinned by merohedry, described by m ‖ [001] and 2 ? [001]. According to the results of an X-ray structure determination (2 778 diffractometer data, Rw = 0.047), Li2H3IO6 exhibits a layer structure, with oxygen forming a distorted variant of the sulfur partial structure in molybdenite (MoS2), however, with iodine and lithium in the more (Li) or less (I) distorted octahedral holes. The Li2IO6 packages are connected via strong hydrogen bonds along the edges of distorted trigonal prisms.  相似文献   

14.
A New Oxogermanate: Li8GeO6 ? Li8O[GeO4] Transparent colourless single crystals of Li8GeO6(P63cm, a = 550.09(8), c = 1072.2(3) pm, Z = 2; 4-circle-diffractometer Siemens AED 2, MoKα; 326 Io(hkl), R = 2.4%, Rw = 2.0%), have been prepared. As by-product we always got colourless isometric single crystals of Li4GeO4. For the first time we could grow single crystals of Li8SiO6 of suitable size and quality. Our structure refinement confirms the assumed structure model [2]: Li8GeO6 and Li8SiO6 are isotypic with Li8CoO6[3] (Li8SiO6: a = 542.43(8), c = 1062.6(2) pm, Z = 2; 4-circle-diffractometer Siemens AED 2, MoKα; 306 Io(hkl), R = 3.6%, Rw= 3.0%). The known crystal structure of Li4GeO4 [4] is confirmed and refined (Cmcm, a = 776.6(2), b = 735.7(3), c = 604.9(2) pm, Z = 4; 4-circle-diffractometer Siemens AED 2, MoKα, 298 Io(hkl), R = 1.9%, Rw = 1.4%). The Madelung Part of Lattice Energy, MAPLE, and Effective coordination-Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated.  相似文献   

15.
The First Diniobate with ‘Isolated’ Anions: KLi4[NbO5]=K2Li8[Nb2O10] [1] . By heating of well ground mixtures of the binary oxides [K2O, Li2O, Nb2O5, K:Li:Nb=1.1:4.4:1, Pt-tube, 1100°C, 3d] colourless, triclinic single crystals of KLi4NbO5 have been prepared for the first time: space group P1 (Nr. 2) with a=816.9(2) pm, b=592.2(2) pm, c=589.7(2) pm, α=121.00(2)º, β=91.78(2)°, γ=99.23(2)°, Z=2. The crystal structure was solved by four-cycle diffractometer data [Mo-Kα , 1386 from 1386 Io(hkl), R=3.4%, Rw=2.6%], parameters see text. Characteristic for this structure are “isolated” groups of [Nb2O10] and the tetrahedral coordination of Li(1), Li(2), and Li(3). Li(4) has a tetragonal-pyramidal coordination. The structural relations are deduced by Schlegel Diagrams. The Madelung Part of Lattice Energy, MAPLE, the Effective Coordination Numbers, ECoN and the charge distribution have been calculated and discussed.  相似文献   

16.
On Quaternary Oxotungstates (VI). Na6Li2[W2O10] — a Ditungstate For the first time, Na6Li2[W2O10] has been prepared by annealing mixtures of WO3, Na2O and Li2O with W:Na:Li = 1:3:1 [closed Pt-tube in quartz-glass ampoule, 840°C, 60 d (single crystals)]. The colourless crystals are of squatted shape. The structure determination [1813/I0(h kl), four-cycle diffractometer PW 1100 (Fa. Philips), ω-scan, AgKα, R = 8.32%, absorption not considered] confirms the space group P1 with a = 784.66(11), b = 602.53(7) c, = 563.81(11) pm α = 106.784(14)°, β = 114.548(14)°, γ = 91.082(13)°, Z = 2, dx = 4.92 g · cm?3, dpyk = 4.85 g · cm?3. The structure may be described as a distorted derivative of the NaCl-type. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated and discussed.  相似文献   

17.
The First Tetraferrate(III): K14[Fe4O13] For the first time K14[Fe4O13] was obtained by annealing intimate mixtures of K2O and LiFeO2 (molar ratio 2.2:1) in closed Ni-cylinders (6 months, 610°C) in the form of yellow-brown single crystals. The structure determination (four circle diffractometer, MoKα, 3377 of 3377 Io(hkl); R = 4,52%, Rw = 2,53%) confirms the space group P21/c; a = 677.9, b = 2956.2, c = 672,1 pm, β = 120.31°, Z = 2. Essential part of the structure are tetranuclear [Fe4O13]14?-groups, oligomers consisting of four corner-sharing FeO4-tetrahedra. Within the structure these groups are connected by two crystallographically distinct K-particles thus forming bands which are arranged according to a ?closest packing of bands”? interconnected by the rest of the K-particles. The structure is described via Schlegel-diagrams. It is isotypic with Na14[Al4O13].  相似文献   

18.
On Copper‐tetrahydrogen‐decaoxo‐diperiodate‐hexahydrate CuH4I2O10·6H2O: Crystal Structure, Vibrational Spectroscopy and Thermal Analysis By crystallization from a strongly acidic aqueous solution copper‐tetrahydrogen‐decaoxodiperiodate‐hexahydrate CuH4I2O10· 6H2O has been obtained. In the structure of this compound (S.G. P 21/c, Nr.14), Z = 2, a = 1060.2(2) pm, b = 551.1(1) pm, c = 1164.7(2) pm, β = 111, 49(3)°) centrosymmetric [H4I2O10]2— anions in the form of two edge sharing octahedra form layers via hydrogen bonds originating from the acidic, trans‐configurated OH groups of the anions. Raman spectra are given and analyzed with respect to the internal vibrations of the periodate anion. The dehydration of the compound takes place via CuH4I2O10·3H2O and Cu(H2IO5)2 which decomposes at 170 °C to Cu(IO3)2.  相似文献   

19.
On Quaternary Oxoplumbates(IV). On the Knowledge of Rb2Li14[Pb3O14] and Cs2Li14[Pb3O14] For the first time, Rb2Li14[Pb3O14] and Cs2Li14[Pb3O14] have been prepared by heating of mixtures of Li2O, β-?PbO2”? and Rb2PbO3, Cs2PbO3 respectively with Li:Pb:A = 14:3:2, (A = Rb, Cs). [Ag-cylinders, sealed under vacuum in Duran-glass ampoule, 590 and 550°C, 40 d, powder (650°C, 200 d, single crystals of Rb2Li14[Pb3O14])]. Rb2Li14[Pb3O14] is nearly colourless with ivory nuance, Cs2Li14[Pb3O14] is pale yellow. According to powder and single crystal investigations, both are isotypic with K2Li14[Pb3O14]. Structure refinement of Rb2Li14[Pb3O14]: 1015 symmetry independent reflexions, four-circle-diffraktometer PW 1100 (Fa. Philips), ω-scan, MoKα, R = 5.73%, RW = 5.33%, absorption not considered, space group Immm with a = 1284.71(9), b = 793.90(4), c = 727,35(5) pm, dx-ray = 4.99 g · cm?3, dpyc = 5.01 g · cm?3, Z = 2. Cs2Li14[Pb3O14]: a = 1295.28(12), b = 796.69(8), c = 732.44(7) pm, dx-ray = 5.31 g · cm?3, dpyc = 5.28 g · cm?3, Z = 2. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Effective Ionic Radii, MEFIR, are calculated.  相似文献   

20.
A New Nesoindate: KNa9In2O8 = KNa9[InO4]2 We prepared hitherto unknown KNa9[InO4]2 (colourless, transparent single crystals) from NaIn, Na2O2, and ?K2O2”? (molar ratio NaIn:Na2O2:?K2O2”? = 2:3.5:0.6, Ag-cylinder, 460°C, 6d). A new type of structure is found. The single crystal data are: Pnma, a = 1802.4(3), b = 729.5(2), c = 907.9(3) pm; Z = 4 [four-circle diffractometer PW 1100, MoKα; 1856 out of 1870 I0(hkl); R = 3.7% and Rw = 3.4%]. The Madelung Part of Lattice Energy, MAPLE, is calculated and discussed.  相似文献   

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